The World Health Organization announced last month that it is recommending the use of indoor spraying with the pesticide DDT, or dichlorodiphenyltrichloroethane, to help control malaria in regions with high rates of the disease. The agency stopped promoting use of DDT in the early 1980s because of increased concerns about its environmental and health effects.
DDT became widely used as an agricultural pesticide in the 1930s but fell out of favor because of concerns about its effects on wildlife and human health. However, proponents of indoor residual spraying (IRS), which involves applying long-acting insecticides on the walls and roofs of houses and domestic animal shelters, say the environmental impact of such use is minimal.
Stephenson J. DDT Returns. JAMA. 2006;296(15):1830. doi:10.1001/jama.296.15.1830-a